The present invention relates to an elevator having an electric power feeding apparatus.
In order to reduce the space for installing an elevator, it is known to the skilled in the art that a driving mechanism for the elevator is installed together in the counter weight and the machinery house to be provided for accommodating the driving mechanism is eliminated. Examples related to this technology are disclosed in the articles, Japanese Patent Laid-Open Number 6-255959 (1994), Japanese Patent Laid-Open Number 7-137963 (1995), Japanese Patent Laid-Open Number 7-137964 (1995), Japanese Patent Laid-Open Number 9-124259 (1997) and Japanese Patent Laid-Open Number 2000-255932 (2000).
Further, what is known publicly include several technologies such as the electric power to be consumed at the car of the elevator is supplied via electrical contact by the electric power supply elements composed of electro-conduction materials or is supplied via contact-less electric feeder by coils and/or transformers. According to those electric power-feeding technologies, it will be appreciated that electric power can be supplied to the car without power feeding cables. Several examples of those technologies are disclosed in the articles, Japanese Patent Laid-Open Number 57-112275 (1982) and Japanese Patent Laid-Open Number 5-294568 (1993).
In case that a driving mechanism for the elevator is mounted on to the counter weight, it is preferable to supply the electric power to the counter weight without using the electric power feeding cable in order to reduce further the space occupied by the installation of the elevator. As for the technologies disclosed in Japanese Patent Laid-Open Number 57-112275 (1982) and Japanese Patent Laid-Open Number 5-294568 (1993), there found the following problems in applying them to the electric power feeding to the counter weight because they are directed for the application for feeding the electric power to the car.
The car and the counter weight are coupled and linked together by a rope, and thus, the positioning accuracy for the counter weight makes lower due to the extension of the rope when attempting to adjust the position of the car. Therefore, the relative position between the power transmission part and the power receiving part of the electric power feeding apparatus may be out of alignment due to the extension of the rope in relative to the electric power feeding to the counter weight. As a result, there are such problems that the efficiency in electric power feeding may be reduced or the electric power feeding itself may be made disabled.
As described above, it is difficult to apply the prior art technologies directly to the electric power feeding to the counter weight due to its low reliability. Thus, even in installing a driving mechanism onto the counter weight, it is required to supply the electric power separately to the counter weight, which leads to a limited amount of reduction in the space occupied by the elevator. In case of applying the prior art technologies, the power transmission part and the power generation apparatus for supplying the electric power, which is to be transferred from the power transmission part to the power receiving part, to the power transmission part are installed within the hoist way inevitably. Thus, the reduction of the space occupied by the elevator may be limited due to the power transmission part and the power generation apparatus.